#include <iostream>
using namespace std;
int main()
{
	int num,total;
	short int m,t,s,fin;
	cin>>m>>t>>s;
	if (t==0) cout<<0<<endl;
	else
	{
		for (num=1;total<s;num++)
		{
			total =t*num;
		}
		num =num-1;
		if (num>m) cout<<0<<endl;
		else
		{
			fin =m-num;
			cout<<fin<<endl;
		}
	}
	return 0;
}
